Actually it's readable everywhere, as it's just an xml-file that acts like a kind of pointer to the *.mp4 file. I replaced .qtl in the URL with .mp4 and downloaded and viewed that file instead.
I'm using Ubuntu Gutsy, it came up in the browser but didn't play, but I right-clicked and chose "Open in Movie Player" and then Totem popped up and it played just fine.
Steve